HIGH
RubyGems version Ruby 2.2 series: 2.2.9 and earlier, Ruby 2.3 series: 2.3.6 and earlier, Ruby 2.4 series: 2.4.3 and earlier, Ruby 2.5 series: 2.5.0 and earlier, prior to trunk revision 62422 contains a Improper Verification of Cryptographic Signature vulnerability in package.rb that can result in a mis-signed gem could be installed, as the tarball would contain multiple gem signatures.. This vulnerability appears to have been fixed in 2.7.6.
http://blog.rubygems.org/2018/02/15/2.7.6-released.html
http://lists.opensuse.org/opensuse-security-announce/2019-07/msg00036.html
https://access.redhat.com/errata/RHSA-2018:3729
https://access.redhat.com/errata/RHSA-2018:3730
https://access.redhat.com/errata/RHSA-2018:3731
https://access.redhat.com/errata/RHSA-2019:2028
https://github.com/rubygems/rubygems/commit/f5042b879259b1f1ce95a0c5082622c646376693
https://lists.debian.org/debian-lts-announce/2018/04/msg00000.html
https://lists.debian.org/debian-lts-announce/2018/04/msg00001.html
https://lists.debian.org/debian-lts-announce/2018/04/msg00023.html
https://lists.debian.org/debian-lts-announce/2018/07/msg00012.html
https://lists.debian.org/debian-lts-announce/2019/05/msg00028.html
https://usn.ubuntu.com/3621-1/
Source: MITRE
Published: 2018-03-13
Updated: 2019-05-20
Type: CWE-347
Base Score: 7.5
Vector: AV:N/AC:L/Au:N/C:P/I:P/A:P
Impact Score: 6.4
Exploitability Score: 10
Severity: HIGH
Base Score: 9.8
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Impact Score: 5.9
Exploitability Score: 3.9
Severity: CRITICAL